/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.netbeans.modules.localhistory.store;

import java.io.File;

/**
 *
 * @author Tomas Stupka
 */
public class LocalHistoryStoreFactory {

    private static LocalHistoryStoreFactory instance;    
    private static LocalHistoryStore storage;
         
    /** Creates a new instance of LocalHistoryStorageFactory */
    private LocalHistoryStoreFactory() {
    } 
    
    public static LocalHistoryStoreFactory getInstance() {
        if(instance == null) {
            instance = new LocalHistoryStoreFactory();
        }
        return instance;
    } 

    /**
     * Creates the storage
     * @return
     */
    public synchronized LocalHistoryStore createLocalHistoryStorage() {
        return createLocalHistoryStorage(true);
    }

    /**
     * Creates the storage if it already exists, otherwise return null
     * @param force - force creation
     * @return
     */
    public synchronized LocalHistoryStore createLocalHistoryStorage(boolean force) {
        if(!force) {
            File root = LocalHistoryStoreImpl.getStorageRootFile();
            if(!root.exists()) return null;
        }
        if(storage == null) {
            storage = new LocalHistoryStoreImpl();
        }
        return storage;
    }
    
}
